Crushing apples to a pulp is a hard but essential task in order to then press the pulp to extract the juice.
Many of us start by using a kitchen food processor, and although it is effective, it is also time consuming because the container only lets you pulp a few apples at a time.
A larger scale solution is a pulpmaster.
Pulpmasters can be purchased for less than £25.00
This is the technique I use myself, but pulpmasters do have their drawbacks. If the bucket is knocked and the blade hits the walls of the bucket, or if there is a stone amongst the apples, the results can be spectacular at best and downright dangerous at worst. They are fast and efficient and if you take care, they are easy to use.
Alternatively homemade pulpers are made by buidling what is essentially a mangle with nails or sharpened bolt heads sticking out of the rollers. The fruit is pushed through the gap between the rollers and pulped. These are pulping machines are also known as scratters.
The other method is to crush your apples with a grindstone. You will see these in museums but I have never seen a grindstone press available for purchase.